Series electrical connections



Sept. 13, 1966 R. F. COBAUGH SERIES ELECTRICAL CONNECTIONS 5 Sheets-Sheet 1 Filed Aug. 17, 1965 FIG. 2A

Sept. 13, 1966 R. F. COBAUGH SERIES ELECTRICAL CONNECTIONS 5 Sheets-Sheet 2 Filed Aug. 17. 1965 p 1966 R. F. COBAUGH SERIES ELECTRICAL CONNECTIONS 5 Sheets-Sheet 5 Filed Aug. 17, 1965 United States Patent 3,273,102 SERIES ELECTRICAL CONNECTIONS Robert Franklin Cobaugh, Hershey, Pa., assignor to AMP Incorporated, Harrisburg, Pa. Filed Aug. 17, 1965, Ser. No. 480,442 2 Claims. (Cl. 339-48) This application is a continuation-in-part of my copending application Serial No. 338,663, filed January 20, 1964, for Electrical Connections.

This invention relates to an improved terminal clip for making clip-type electrical connections in accordance with the general teaching of my co-pending application Serial No. 171,074, filed February 5, 1962.

An object of the invention is to provide an improved terminal clip for making clip-type electrical connections. A further object is to provide a terminal clip for connecting an intermediate portion of a conductor to a ter minal post. A further object is to provide an improved electrical connection. A still further object is to provide an improved series connection among a plurality of terminal posts.

These and other objects of the invention are achieved in a preferred embodiment thereof comprising a terminal clip having a Web portion and sidewalls extending from the longitudinal edges of the web. These sidewalls are reversely curled inwardly towards each other and towards the underside of the web. The clip is adapted to be moved axially onto the terminal post and to drag the wire, which is to be connected to a post, over the surface of the post. The web is provided with outwardly cupped or deformed portions at each of its ends between the sidewalls. These outwardly deformed portions extend in the opposite direction from the sidewalls and provide sloping surfaces which extend towards the plane of the web and towards each other. These sloping surfaces function as strain relief and/or insulation supporting means for the conductor. In an electrical connection in accordance with the invention, the terminal clip is axially mounted on the post and the conductor extends over one of the outwardly cupped portions of the web, between the web and the surface of the post, and emerges from confined relationship through the other outwardly deformed portion of the web.

In the drawing:

FIGURE 1 is a perspective view of a short section of a strip of terminal clips in accordance with the invention;

FIGURE 2 is a sectional side view, taken along the lines 2-2 of FIGURE 2A, of a preferred form of terminal clip;

FIGURE 2A is an end view looking in the direction of the arrows 2A-2A of FIGURE 2;

FIGURE 3 shows an electrical circuit among a plurality of terminal posts with the connections between the conductor and the terminal post being in accordance with the present invention, the conductor in FIGURE 3 being a film-coated wire of the type commonly referred to as magnet wire;

FIGURE 4 is a view similar to FIGURE 3 but showing a circuit in which the wire has a conventional relatively thick insulating film or sheath thereon;

FIGURES 5 and 6 are views taken along the lines 55 and 66 of FIGURES 3 and 4 respectively; and

'FIGURE 7 is a view showing the manner of making an electrical connection in accordance with the invention.

Referring first to FIGURES 1 and 2, a terminal clip 2 in accordance with the invention has .a web portion 4 having sidewalls 6 extending from its longitudinal edges. These sidewalls are inwardly curled towards each other and towards the underside of the web as shown at 8. The distance between the edges of the curled portions of the sidewalls and the underside of the web is substantially equal to, or slightly less than, the thickness of the terminal post 18 so that the clip can be telescopically moved onto the post and will hold a wire, confined between the surface of the post in the internal surface of the web, against the post to establish a reliable, lowresistance electrical connection.

The sidewalls are cut away as shown at 10 at one end of the clip, herein referred to as the leading end, to provide clearance, in a wired terminal board, for conductors which may extend past individual terminal clips mounted on the posts of the board. The web has outwardly cupped portions 12, 14 at each end and between the sidewalls 6, these outwardly cupped portions providing sloping surfaces 13, .15 which extend towards the surface of the web and towards each other. If desired, serrations 16 may be provided on the internal surface of the web to improve the mechanical strength and the electrical properties of the electrical connection.

An electrical connection in accordance with the invention is made by moving one of the clips 2 along a predetermined path past an intermediate portion of a transversely extending conductor and onto the terminal post 18 to which it is desired to electrically connect the conductor as illustrated in FIGURE 7. During such movement of the clip, its leading end will engage and drag a portion of the conductor onto the post so that in the finished connection (FIGURE 3) the conductor will enter confined relationship between the web and the surface of the post through the outwardly cupped portion 12 at the leading end of the clip, will extend along the surface of the post, and will emerge from confined relationship through the outwardly cupped portion 14 of the web.

Ordinarily, the clip is moved along its path and applied to the post by means of a suitable hand tool or automatic machine. A hand tool particularly intended for use with clips of the type herein disclosed is described in detail in my co-pending application Serial No. 367,479, filed May 14, 1964. Clip-type electrical connections in accordance with the invention can also be made with an automatic wiring machine of the type described in US. Patent 3,186,077, and as explained in the bridging paragraph of columns 17 and 18 of that patent.

In FIGURE 3 it is assumed that the conductor 20 is of the type provided with a relatively thin film of insulating material such as Formvar (polyvinyl formal resin). Application Serial No. 367,479 shows one form of tool having means for partially removing such thin film insulation from the portion of the wire which is to be electrically connected to a terminal post. Clips in accordance with the invention can also be used with wires 22 (FIGURE 4) which have a conventional relatively thick insulating material. Where wires of this type are being used, the insulating sheath can be stripped from the portion of the wire which is to be connected to a terminal post prior to making the electrical connection as is also disclosed in application Serial No. 367,479.

As will be apparent from FIGURES 3 and 4, the outwardly cupped portions 13, 14 of the web function as lead-in and strain relief means for the wire at each end of the terminal clip and avoid abrupt bending of the wire which would result in extremely high bending stresses and possible fracture. In the case of a conductor 22 having a conventional thick insulating sheath thereon, the outwardly cupped portions also function as insulation supporting means for the portions of the insulation adjacent of the stripped portions of the wire.

It will be understood that more than one clip can be applied to a single terminal post as is shown in FIGURE 3. It will also be understood that the left-hand end of the wire 20 in FIGURE 3 will be disposed adjacent to the outwardly cupped portion 12 of the leading end of 89 the connector of the terminal while the right-hand end of this wire will emerge from and will be disposed adjacent to the outwardly cupped portion 14 of the terminal clip and the righthand post. In the case of the intermediate electrical connections, the wire 20 enters confined relationship at the leading end of the terminal clip, extends upwardly along the terminal post, and emerges from confined relationship in the trailing end of the clip.

The advantages of clips in accordance with the invention can readily be perceived from an inspection of FIG- URES 3 and 4 and from a consideration of the number of terminal clips which would be required, and the number of electrical interfaces which would be established, if conventional terminal clips were used to establish the same circuits shown in FIGURES 3 and 4. In FIG- URE 4, the electrical circuit extends from the left-hand post to the third post (going from left to right) to the fourth post and terminates at the sixth post. Only one wire is required for this circuit and only four terminal clips are used. Furthermore, the path of current flow from the first post to the sixth post involves only two electrical interfaces, namely, the interface on the first post and the interface on the sixth post.

If conventional clips, as previously known, were used for the circuit of FIGURE 4, then it would be necessary to use three separate wires, one such lead extending from the first post to the third post, a second lead extending from the third post to the fourth post and a third lead extending from the fourth post to the sixth post. It would also be necessary to use two terminal clips on the third and fourth terminal'posts rather than one terminal clip and the path of current flow from the first post to the sixth post would involve six electrical interfaces each of which would contribute to the total resistance of the circuit.

' Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made with-out departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective against the prior art.

I claim:

1. A series electrical hook-up among a plurality of terminal posts, said posts being straight and having a uniform cross-section throughout their lengths, said hookup comprising a conductor having a clip-type electrical connection with each of said posts, the clips of said electrical connections having a web portion disposed against one side of the associated terminal post and having outwardly deformed portions at each end of the web, said conductor, in each electrical connection, extending through the outwardly deformed portion which is adjacent to the base of the post, thence axially along a surface of the post and between said surface and said web, and emerging from confined relationship through the outwardly deformed portion of said web which is remote from the base of the post.

2. A plurality of terminal posts electrically connected in series to each other by a single conductor, said posts each having a fixed end and a free end, said posts being straight and having a uniform cross-section throughout their lengths, said conductor being electrically connected to said posts by terminal clips, each clip comprising a web portion and post embracing sidewalls extending from said web portion, each of said clips being telescopically mounted on one of said posts, said conductor, in each electrical connection, extending along the axis of the post and being confined between the web portion of the clip and a surface of the post, said conductor emerging from confined relationship at the end of the clip which is remote from the fixed end of the post and extending to the next electrical connection of the series.

References Cited by the Examiner UNITED STATES PATENTS 2,134,775 11/1938 Bergan 339256 X 2,780,794 2/1957 Cresson 339-276 3,071,750 1/1963 Heselwood 339--276 X 3,122,604 2/1964 Cook et al. 339-256 X EDWARD C. ALLEN, Primary Examiner.

W. DONALD MILLER, Examiner. 

1. A SERIES ELECTRICAL HOOK-UP AMONG A PLURALITY OF TERMINAL POSTS, SAID POSTS BEING STRAIGHT AND HAVING A UNIFORM CROSS-SECTION THROUGHOUT THEIR LENGTHS, SAID HOOKUP COMPRISING A CONDUCTOR HAVING A CLIP-TYPE ELECTRICAL CONNECTION WITH EACH OF SAID POSTS, THE CLIPS OF SAID ELECTRICAL CONNECTIONS HAVING A WEB PORTION DISPOSED AGAINST ONE SIDE OF THE ASSOCIATED TERMINAL POST AND HAVING OUTWARDLY DEFORMED PORTIONS AT EACH END OF THE WEB, SAID CONDUCTOR, IN EACH ELECTRICAL CONNECTION, EXTENDING THROUGH THE OUTWARDLY DEFORMED PORTION WHICH IS ADJACENT TO THE BASE OF THE POST, THENCE AXIALLY ALONG A SURFACE OF THE POST AND BETWEEN SAID SURFACE AND SAID WEB, AND EMERGING FROM CONFINED RELATIONSHIP THROUGH THE OUTWARDLY DEFORMED PORTION OF SAID WEB WHICH IS REMOTE FROM THE BASE OF THE POST. 